In Organizer, use Edit...Preferences...Files and uncheck the "Rotate Files using Metadata" option.

From the Help file:
Rotate JPEGs Using Orientation Metadata/Rotate TIFFs Using Orientation Metadata
When these options are selected, the orientation metadata of the image is updated to rotate the image. The image data is untouched; the rotation is specified by just changing the metadata. Rotating an image using its metadata is a faster process than rotating the image itself.Not all applications recognize orientation metadata. If you plan to import your images into such applications, leave these options deselected.